/*
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.jctools.util;

import com.jfirer.jnet.common.util.UNSAFE;

import java.util.function.LongBinaryOperator;
import java.util.function.LongUnaryOperator;

abstract class PaddedAtomicLongL1Pad extends Number implements java.io.Serializable
{
    private static final long serialVersionUID = 1;
    byte b000, b001, b002, b003, b004, b005, b006, b007;//  8b
    byte b010, b011, b012, b013, b014, b015, b016, b017;// 16b
    byte b020, b021, b022, b023, b024, b025, b026, b027;// 24b
    byte b030, b031, b032, b033, b034, b035, b036, b037;// 32b
    byte b040, b041, b042, b043, b044, b045, b046, b047;// 40b
    byte b050, b051, b052, b053, b054, b055, b056, b057;// 48b
    byte b060, b061, b062, b063, b064, b065, b066, b067;// 56b
    byte b070, b071, b072, b073, b074, b075, b076, b077;// 64b
    byte b100, b101, b102, b103, b104, b105, b106, b107;// 72b
    byte b110, b111, b112, b113, b114, b115, b116, b117;// 80b
    byte b120, b121, b122, b123, b124, b125, b126, b127;// 88b
    byte b130, b131, b132, b133, b134, b135, b136, b137;// 96b
    byte b140, b141, b142, b143, b144, b145, b146, b147;//104b
    byte b150, b151, b152, b153, b154, b155, b156, b157;//112b
    byte b160, b161, b162, b163, b164, b165, b166, b167;//120b
    byte b170, b171, b172, b173, b174, b175, b176, b177;//128b
}

abstract class PaddedAtomicLongL1Field extends PaddedAtomicLongL1Pad
{
    private final static long VALUE_OFFSET = UNSAFE.unsafe.objectFieldOffset(PaddedAtomicLongL1Field.class, "value");
    private volatile     long value;

    public void spVal(long v)
    {
        UNSAFE.putLong(this, VALUE_OFFSET, v);
    }

    public void soVal(long v)
    {
        UNSAFE.unsafe.putLongRelease(this, VALUE_OFFSET, v);
    }

    public void svVal(long v)
    {
        value = v;
    }

    public long lvVal()
    {
        return value;
    }

    public long lpVal()
    {
        return UNSAFE.getLong(this, VALUE_OFFSET);
    }

    public boolean casVal(long expectedV, long newV)
    {
        return UNSAFE.unsafe.compareAndSetLong(this, VALUE_OFFSET, expectedV, newV);
    }

    public long getAndSetVal(long v)
    {
        return UNSAFE.unsafe.getAndSetLong(this, VALUE_OFFSET, v);
    }

    public long getAndAddVal(long delta)
    {
        return UNSAFE.unsafe.getAndAddLong(this, VALUE_OFFSET, delta);
    }
}

abstract class PaddedAtomicLongL2Pad extends PaddedAtomicLongL1Field
{
    byte b000, b001, b002, b003, b004, b005, b006, b007;//  8b
    byte b010, b011, b012, b013, b014, b015, b016, b017;// 16b
    byte b020, b021, b022, b023, b024, b025, b026, b027;// 24b
    byte b030, b031, b032, b033, b034, b035, b036, b037;// 32b
    byte b040, b041, b042, b043, b044, b045, b046, b047;// 40b
    byte b050, b051, b052, b053, b054, b055, b056, b057;// 48b
    byte b060, b061, b062, b063, b064, b065, b066, b067;// 56b
    byte b070, b071, b072, b073, b074, b075, b076, b077;// 64b
    byte b100, b101, b102, b103, b104, b105, b106, b107;// 72b
    byte b110, b111, b112, b113, b114, b115, b116, b117;// 80b
    byte b120, b121, b122, b123, b124, b125, b126, b127;// 88b
    byte b130, b131, b132, b133, b134, b135, b136, b137;// 96b
    byte b140, b141, b142, b143, b144, b145, b146, b147;//104b
    byte b150, b151, b152, b153, b154, b155, b156, b157;//112b
    byte b160, b161, b162, b163, b164, b165, b166, b167;//120b
    byte b170, b171, b172, b173, b174, b175, b176, b177;//128b
}

/**
 * A padded version of the {@link java.util.concurrent.atomic.AtomicLong}.
 */
public class PaddedAtomicLong extends PaddedAtomicLongL2Pad
{
    /**
     * Creates a new PaddedAtomicLong with initial value {@code 0}.
     */
    public PaddedAtomicLong()
    {
    }

    /**
     * Creates a new PaddedAtomicLong with the given initial value.
     *
     * @param initialValue the initial value
     */
    public PaddedAtomicLong(long initialValue)
    {
        svVal(initialValue);
    }

    /**
     * Gets the current value.
     *
     * @return the current value
     * @see java.util.concurrent.atomic.AtomicLong#get()
     */
    public long get()
    {
        return lvVal();
    }

    /**
     * Sets to the given value.
     *
     * @param newValue the new value
     * @see java.util.concurrent.atomic.AtomicLong#set(long)
     */
    public void set(long newValue)
    {
        svVal(newValue);
    }

    /**
     * Eventually sets to the given value.
     *
     * @param newValue the new value
     * @see java.util.concurrent.atomic.AtomicLong#lazySet(long)
     */
    public void lazySet(long newValue)
    {
        soVal(newValue);
    }

    /**
     * Atomically sets to the given value and returns the old value.
     *
     * @param newValue the new value
     * @return the previous value
     * @see java.util.concurrent.atomic.AtomicLong#getAndSet(long)
     */
    public long getAndSet(long newValue)
    {
        return getAndSetVal(newValue);
    }

    /**
     * Atomically sets the value to the given updated value
     * if the current value {@code ==} the expected value.
     *
     * @param expect the expected value
     * @param update the new value
     * @return {@code true} if successful. False return indicates that
     * the actual value was not equal to the expected value.
     * @see java.util.concurrent.atomic.AtomicLong#compareAndSet(long, long)
     */
    public boolean compareAndSet(long expect, long update)
    {
        return casVal(expect, update);
    }

    /**
     * Atomically sets the value to the given updated value
     * if the current value {@code ==} the expected value.
     *
     * <p><a href="package-summary.html#weakCompareAndSet">May fail
     * spuriously and does not provide ordering guarantees</a>, so is
     * only rarely an appropriate alternative to {@code compareAndSet}.
     *
     * @param expect the expected value
     * @param update the new value
     * @return {@code true} if successful
     * @see java.util.concurrent.atomic.AtomicLong#weakCompareAndSet(long, long)
     */
    public boolean weakCompareAndSet(long expect, long update)
    {
        return casVal(expect, update);
    }

    /**
     * Atomically increments the current value by 1.
     *
     * @return the previous value
     * @see java.util.concurrent.atomic.AtomicLong#getAndIncrement()
     */
    public long getAndIncrement()
    {
        return getAndAddVal(1L);
    }

    /**
     * Atomically decrements the current value by 1.
     *
     * @return the previous value
     * @see java.util.concurrent.atomic.AtomicLong#getAndDecrement()
     */
    public long getAndDecrement()
    {
        return getAndAddVal(-1L);
    }

    /**
     * Atomically adds to the current value the given value.
     *
     * @param delta the value to add
     * @return the previous value
     * @see java.util.concurrent.atomic.AtomicLong#getAndAdd(long)
     */
    public long getAndAdd(long delta)
    {
        return getAndAddVal(delta);
    }

    /**
     * Atomically increments the current value by one.
     *
     * @return the updated value
     * @see java.util.concurrent.atomic.AtomicLong#incrementAndGet()
     */
    public long incrementAndGet()
    {
        return getAndAddVal(1L) + 1L;
    }

    /**
     * Atomically decrements the current value by one.
     *
     * @return the updated value
     * @see java.util.concurrent.atomic.AtomicLong#decrementAndGet()
     */
    public long decrementAndGet()
    {
        return getAndAddVal(-1L) - 1L;
    }

    /**
     * Atomically adds to current value te given value.
     *
     * @param delta the value to add
     * @return the updated value
     * @see java.util.concurrent.atomic.AtomicLong#addAndGet(long)
     */
    public long addAndGet(long delta)
    {
        return getAndAddVal(delta) + delta;
    }

    /**
     * Atomically updates the current value with the results of
     * applying the given function, returning the previous value. The
     * function should be side-effect-free, since it may be re-applied
     * when attempted updates fail due to contention among threads.
     *
     * @param updateFunction a side-effect-free function
     * @return the previous value
     * @see java.util.concurrent.atomic.AtomicLong#getAndUpdate(LongUnaryOperator)
     */
    public long getAndUpdate(LongUnaryOperator updateFunction)
    {
        long prev, next;
        do
        {
            prev = lvVal();
            next = updateFunction.applyAsLong(prev);
        } while (!casVal(prev, next));
        return prev;
    }

    /**
     * Atomically updates the current value with the results of
     * applying the given function, returning the updated value. The
     * function should be side-effect-free, since it may be re-applied
     * when attempted updates fail due to contention among threads.
     *
     * @param updateFunction a side-effect-free function
     * @return the updated value
     * @see java.util.concurrent.atomic.AtomicLong#updateAndGet(LongUnaryOperator)
     */
    public long updateAndGet(LongUnaryOperator updateFunction)
    {
        long prev, next;
        do
        {
            prev = lvVal();
            next = updateFunction.applyAsLong(prev);
        } while (!casVal(prev, next));
        return next;
    }

    /**
     * Atomically updates the current value with the results of
     * applying the given function to the current and given values,
     * returning the previous value. The function should be
     * side-effect-free, since it may be re-applied when attempted
     * updates fail due to contention among threads.  The function
     * is applied with the current value as its first argument,
     * and the given update as the second argument.
     *
     * @param v the update value
     * @param f a side-effect-free function of two arguments
     * @return the previous value
     * @see java.util.concurrent.atomic.AtomicLong#getAndAccumulate(long, LongBinaryOperator)
     */
    public long getAndAccumulate(long v, LongBinaryOperator f)
    {
        long prev, next;
        do
        {
            prev = lvVal();
            next = f.applyAsLong(prev, v);
        } while (!casVal(prev, next));
        return prev;
    }

    /**
     * {@link java.util.concurrent.atomic.AtomicLong#accumulateAndGet(long, LongBinaryOperator)}
     */
    public long accumulateAndGet(long x, LongBinaryOperator f)
    {
        long prev, next;
        do
        {
            prev = lvVal();
            next = f.applyAsLong(prev, x);
        } while (!casVal(prev, next));
        return next;
    }

    /**
     * Returns the String representation of the current value.
     *
     * @return the String representation of the current value
     */
    @Override
    public String toString()
    {
        return Long.toString(lvVal());
    }

    /**
     * Returns the value as an {@code int}.
     *
     * @see java.util.concurrent.atomic.AtomicLong#intValue()
     */
    @Override
    public int intValue()
    {
        return (int) lvVal();
    }

    /**
     * Returns the value as a {@code long}.
     *
     * @see java.util.concurrent.atomic.AtomicLong#longValue()
     */
    @Override
    public long longValue()
    {
        return lvVal();
    }

    /**
     * Returns the value of a {@code float}.
     *
     * @see java.util.concurrent.atomic.AtomicLong#floatValue()
     */
    @Override
    public float floatValue()
    {
        return (float) lvVal();
    }

    /**
     * Returns the value of a {@code double}.
     *
     * @see java.util.concurrent.atomic.AtomicLong#doubleValue()
     */
    @Override
    public double doubleValue()
    {
        return (double) lvVal();
    }
}
